They come into the station, march to the platform and stand facing the tracks in the exact spot — measured to precision over years of practice — where they are absolutely, positively sure a car door will appear when the train stops.

Only sometimes the train comes and — d’oh! — it has only four cars and stops waaay down the platform.

So the riders run, briefcases and purses swinging at their sides, to try to squeeze into an end car. Some get on. Some harrumph in frustration, left to try their luck with the next train.